University of Virginia Library

26.14. 14. In what instances Marriages between Relatives shall be regulated
by the Laws of Nature: and in what instances by the civil Laws.

With regard to the prohibition of marriage between relatives, it is a thing extremely delicate to fix exactly the point at which the laws of nature stop and where the civil laws begin. For this purpose we must establish some principles.

The marriage of the son with the mother confounds the state of things: the son ought to have an unlimited respect for his mother, the wife an unlimited respect for her husband; therefore the marriage of the mother to her son would subvert the natural state of both.

Besides, nature has forwarded in women the time in which they are able to have children, but has retarded it in men; and, for the same reason, women sooner lose this ability and men later. If the marriage between the mother and the son were permitted, it would almost always be the case that when the husband was capable of entering into the views of nature, the wife would be incapable.

The marriage between the father and the daughter is contrary to nature, as well as the other; but it is not less contrary, because it has not these two obstacles. Thus the Tartars, who may marry their daughters, [31] never marry their mothers, as we see in the accounts we have of that nation. [32]

It has ever been the natural duty of fathers to watch over the chastity of their children. Entrusted with the care of their education, they are obliged to preserve the body in the greatest perfection, and the mind from the least corruption; to encourage whatever has a tendency to inspire them with virtuous desires, and to nourish a becoming tenderness. Fathers, always employed in preserving the morals of their children, must have a natural aversion to everything that can render them corrupt. Marriage, you will say, is not a corruption; but before marriage they must speak, they must make their persons beloved, they must seduce; it is this seduction which ought to inspire us with horror.

There should be therefore an insurmountable barrier between those who ought to give the education, and those who are to receive it, in order to prevent every kind of corruption, even though the motive be lawful. Why do fathers so carefully deprive those who are to marry their daughters of their company and familiarity?

The horror that arises against the incest of the brother with the sister should proceed from the same source. The desire of fathers and mothers to preserve the morals of their children and families untainted is sufficient to inspire their offspring with a detestation of everything that can lead to the union of the two sexes.

The prohibition of marriage between cousins-german has the same origin. In the early ages, that is, in the times of innocence, in the ages when luxury was unknown, it was customary for children [33] upon their marriage not to remove from their parents, but settle in the same house; as a small habitation was at that time sufficient for a large family; the children of two brothers, or cousins-german, [34] were considered both by others and themselves as brothers. The estrangement then between the brothers and sisters as to marriage subsisted also between the cousins-german. [35] These principles are so strong and no natural that they have had their influence almost over all the earth, independently of any communication. It was not the Romans who taught the inhabitants of Formosa [36] that the marriage of relatives of the fourth degree was incestuous; it was not the Romans that communicated this sentiment to the Arabs; [37] it was not they who taught it to the inhabitants of the Maldivian islands. [38]

But if some nations have not rejected marriages between fathers and children, sisters and brothers, we have seen in the first book, that intelligent beings do not always follow the law of nature. Who could have imagined it! Religious ideas have frequently made men fall into these mistakes. If the Assyrians and the Persians married their mothers, the first were influenced by a religious respect for Semiramis, and the second did it because the religion of Zoroaster gave a preference to these marriages. [39] If the Egyptians married their sisters, it proceeded from the wildness of the Egyptian religion, which consecrated these marriages in honour of Isis. As the spirit of religion leads us to attempt whatever is great and difficult, we cannot infer that a thing is natural from its being consecrated by a false religion.

The principle which informs us that marriages between fathers and children, between brothers and sisters, are prohibited in order to preserve natural modesty in families will help us to the discovery of those marriages that are forbidden by the law of nature, and of those which can be so only by the civil law.

As children dwell, or are supposed to dwell in their father's house, and consequently the son-in-law with the mother-in-law, the father-in-law with the daughter-in-law, or wife's daughter, the marriage between them is forbidden by the law of nature, in this case the resemblance has the same effect as the reality, because it springs from the same cause; the civil law neither can, nor ought to permit these marriages.

There are nations, as we have already observed, among whom cousins-german are considered as brothers, because they commonly dwell in the same house; there are others where this custom is not known. Among the first the marriage of cousins-german ought to be regarded as contrary to nature; not so among the others.

But the laws of nature cannot be local. Therefore, when these marriages are forbidden or permitted, they are, according to the circumstances, permitted or forbidden by a civil law.

It is not a necessary custom for the brother-in-law and the sister-in-law to dwell in the same house. The marriage between them is not then prohibited to preserve chastity in the family; and the law which forbids or permits it is not a law of nature, but a civil law, regulated by circumstances and dependent on the customs of each country: these are cases in which the laws depend on the morals, or customs of the inhabitants.

The civil laws forbid marriages when by the customs received in a certain country they are found to be in the same circumstances as those forbidden by the law of nature; and they permit them when this is not the case. The prohibitions of the laws of nature are invariable, because the thing on which they depend is invariable; the father, the mother and the children necessarily dwell in the same house. But the prohibitions of the civil laws are accidental because they depend on an accidental circumstance, cousins-german and others dwelling in the house by accident.

This explains why the laws of Moses, those of the Egyptians, [40] and of many other nations permitted the marriage of the brother-in-law with the sister-in-law; whilst these very marriages were disallowed by other nations.

In the Indies they have a very natural reason for admitting this sort of marriages. The uncle is there considered as the father and is obliged to maintain and educate his nephew as if he were his own child; this proceeds from the disposition of this people, which is good-natured and full of humanity. This law or this custom has produced another; if a husband has lost his wife, he does not fail to marry her sister: [41] which is extremely natural, for his new consort becomes the mother of her sister's children, and not a cruel stepmother.

Footnotes